Hi.  I have a 2007 Audi A6 2.0 TDI. 140 engine .   For a few months it has been making a noise only from cold which I believe is described as turbo flutter. However for the past week it has been making the same noise even when warm, this is only when changing gear. Two days ago returning from a short trip I was going up hill when I lost the turbo boost completely, managed to get home ok just a couple of miles, left it for an hour and  Started the car again and it was back to just how it was previously,  I have no warning lights and no smoke of any description, I am not a mechanic but I need to get this sorted as I am now worried about driving any distance. I am prepared if necessary to have a new or recon Garrett turbo fitted if that is the problem but before going to that expense I wondered if anyone else has experienced anything similar and if so what was the cause.

Any help or advice would be very much appreciated,     Thanks 

It's definitely worth getting a diagnostic check carried out to see if there are any fault codes stored. If any blades from the turbo have broken off then it could cause the turbo to be intermittent. 

injector  down    

Wondered if that was a considered diagnosis Kev, possibly based on previous experience, or perhaps just a valid stab at it?

I would have thought that injector issues would have been accompanied by smoke from not fully combusted diesel.

If it were mine Colin, I think I would be getting getting this looked at by a trusted local diesel specialist. 

Kind regards,

Gareth.